U.S. patent application number 14/309358 was filed with the patent office on 2015-01-01 for apparatus and method to dynamically adjust electronic braking using tpms.
The applicant listed for this patent is Continental Automotive Systems, Inc.. Invention is credited to Jean-Christophe Deniau, Brian J. Farrell, Matthew D McIntyre.
Application Number | 20150006051 14/309358 |
Document ID | / |
Family ID | 52116397 |
Filed Date | 2015-01-01 |
United States Patent
Application |
20150006051 |
Kind Code |
A1 |
McIntyre; Matthew D ; et
al. |
January 1, 2015 |
APPARATUS AND METHOD TO DYNAMICALLY ADJUST ELECTRONIC BRAKING USING
TPMS
Abstract
The dynamic footprint of a tire is received and the dynamic
footprint is determined by and received from a tire pressure
monitoring (TPM) sensor. A weight or load of the secondary vehicle
attached to the primary vehicle is calculated based at least in
part on the footprint. Instructions to alter the operation of the
braking system of the secondary vehicle based on the calculated
weight or load are transmitted to the secondary vehicle.
Inventors: |
McIntyre; Matthew D; (New
Baltimore, MI) ; Deniau; Jean-Christophe; (Fenton,
MI) ; Farrell; Brian J.; (Troy, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Continental Automotive Systems, Inc. |
Auburn Hills |
MI |
US |
|
|
Family ID: |
52116397 |
Appl. No.: |
14/309358 |
Filed: |
June 19, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61840680 |
Jun 28, 2013 |
|
|
|
Current U.S.
Class: |
701/70 |
Current CPC
Class: |
B60C 23/0488 20130101;
B60C 23/009 20130101; B60C 23/0433 20130101; B60T 8/1887 20130101;
B60T 2240/06 20130101; B60T 8/1725 20130101; B60T 11/108 20130101;
B60T 8/1708 20130101 |
Class at
Publication: |
701/70 |
International
Class: |
B60T 8/17 20060101
B60T008/17; B60T 8/18 20060101 B60T008/18; B60T 11/10 20060101
B60T011/10; B60T 8/172 20060101 B60T008/172 |
Claims
1. A method of dynamically adjusting a braking system of a
secondary vehicle being towed by a primary vehicle, the method
comprising: receiving the dynamic footprint of a tire, the dynamic
footprint being determined by and received from a tire pressure
monitoring (TPM) sensor; calculating a weight or load of the
secondary vehicle attached to the primary vehicle based at least in
part on the footprint; transmitting instructions to alter the
operation of the braking system of the secondary vehicle based on
the calculated weight or load.
2. The method of claim l further comprising making an adjustment to
the braking system of the secondary vehicle.
3. The method of claim 2 wherein the adjustment is changing a
voltage or current.
4. The method of claim 2 wherein the adjustment is opening or
closing a valve in the braking system in the secondary vehicle.
5. An electronic control unit (ECU) disposed in a primary vehicle
and configured to communicate with a tire pressure monitoring (TPM)
sensor in a secondary vehicle, the ECU comprising: an interface; a
receiver coupled to the interface, the receiver configured to
receive the dynamic footprint of a tire, the dynamic footprint
being determined by and received from the TPM sensor; a transmitter
coupled to the interface; a processor coupled to the interface, the
processor configured to calculating a weight or load of the
secondary vehicle attached to the primary vehicle based at least in
part on the footprint, the processor further configured to transmit
instructions to a braking system via the transmitter, the
instructions effective to make an adjustment to the braking system
of the secondary vehicle based on the calculated weight or
load.
7. The ECU of claim 6 wherein the adjustment is a change to a
voltage or current.
8. The ECU of claim 6 wherein the adjustment is an opening or
closing a valve in the braking system of the secondary vehicle.
9. A method of dynamically adjusting a braking system of a
secondary vehicle being towed by a primary vehicle, the method
comprising: determining a dynamic footprint of a tire, the dynamic
footprint of a tire of a secondary vehicle that is attached to a
primary vehicle; transmitting the dynamic footprint to a electronic
control unit, the electronic control unit responsively calculating
a weight or load of the secondary vehicle attached to the primary
vehicle based at least in part on the footprint and transmitting
instructions to alter the operation of the braking system of the
secondary vehicle based on the calculated weight or load.
10. The method of claim 9, further comprising making an adjustment
to the braking system of the vehicle.
11. The method of claim 10 wherein the adjustment is changing a
voltage or current.
12. The method of claim 10 wherein the adjustment is opening or
closing a valve in the braking system of the secondary vehicle.
13. A tire pressure monitoring (TPM) sensor disposed in a secondary
vehicle that communicates with electronic control unit (ECU)
disposed in a primary vehicle, the TPM comprising: an interface; a
transmitter coupled to the interface; a sensing apparatus for
measuring tire pressure; a processor coupled to the interface, the
processor configured to determine a dynamic footprint of a tire
based at least in part on the sensed readings of the sensing
apparatus, the processor further configured to transmit the dynamic
footprint of a tire of a secondary vehicle to the ECU, wherein the
ECU determines the weight of the secondary vehicle based at least
in part of the footprint and the ECU transmits instructions to a
braking system of the secondary vehicle to make an adjustment based
at least in part upon the weight.
14. The TPM sensor of claim 6 wherein the adjustment is a change to
a voltage or current.
15. The TPM sensor of claim 6 wherein the adjustment is an opening
or closing a valve in the braking system of the secondary
vehicle.
16. A non-transitory computer readable medium comprising computer
executable instructions adapted to perform a method, the method
comprising: receiving the dynamic footprint of a tire, the dynamic
footprint being determined by and received from a tire pressure
monitoring (TPM) sensor; calculating a weight or load of the
secondary vehicle attached to the primary vehicle based at least in
part on the footprint; transmitting instructions to alter the
operation of the braking system of the secondary vehicle based on
the calculated weight or load.
17. The non-transitory computer readable medium of claim 16 wherein
the method further comprises making an adjustment to the braking
system of the vehicle.
18. The non-transitory computer readable medium of claim 17 wherein
the adjustment is changing a voltage or current.
19. The non-transitory computer readable medium of claim 17 wherein
the adjustment is opening or closing a valve in the braking system.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This patent claims benefit under 35 U.S.C. .sctn.119 (e) to
U.S. Provisional application No. 61/840,680, filed Jun. 28, 2013
and entitled "Method to Configure Electronic Braking using TPMS,"
the content of which is incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to vehicles and more
particularly to electronic braking systems for automotive
vehicles.
BACKGROUND OF THE INVENTION
[0003] Vehicles equipped with electronic braking systems can adjust
the vehicle braking response to accommodate for various braking
situations. When a vehicle has a trailer attached, the braking
system of the trailer must be adjusted based on the weight of the
trailer.
[0004] However, this adjustment is done manually by the operator.
In most cases, the adjustment of the electric braking system for
the trailer is a "hit or miss". If the weight of the trailer is not
entered properly, then the effectiveness of the braking system is
compromised, creating an unsafe driving condition.
[0005] The driver wants to ensure that the truck pulling the
trailer does not slow down the trailer leading to over use, wear
and tear of the truck braking system. On the other hand, the driver
also wants to ensure that the trailer does not do all the breaking
work leading to over use of the trailer braking system and possibly
handling impacts on the truck. Additionally, if the load on the
trailer is not centered the momentum of the area/side where the
load is located will be greater thus requiring more brake power on
that side.
[0006] Previous approaches have not proven adequate into addressing
these problems. Consequently, some user dissatisfaction with
previous approaches has arisen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present disclosure will become more fully understood
from the detailed description and the accompanying drawings,
wherein:
[0008] FIG. 1 comprises a schematic illustration of a vehicle with
a tire pressure monitoring system of the present invention
according to various embodiments of the present invention;
[0009] FIG. 2 comprises a flowchart of one example of an approach
for adjusting a brake system using a tire pressure monitoring
system of the present invention according to various embodiments of
the present invention;
[0010] FIG. 3 comprises a block diagram of a tire pressure
monitoring sensor that utilizes the approaches described herein
according to various embodiments of the present invention; and
[0011] FIG. 4 comprises a block diagram of an electronic control
unit (ECU) that utilizes the approaches described herein according
to various embodiments of the present invention.
[0012] Skilled artisans will appreciate that elements in the
figures are illustrated for simplicity and clarity. It will further
be appreciated that certain actions and/or steps may be described
or depicted in a particular order of occurrence while those skilled
in the art will understand that such specificity with respect to
sequence is not actually required. It will also be understood that
the terms and expressions used herein have the ordinary meaning as
is accorded to such terms and expressions with respect to their
corresponding respective areas of inquiry and study except where
specific meanings have otherwise been set forth herein.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The following description is merely exemplary in nature and
is in no way intended to limit the disclosure, its application, or
uses. For purposes of clarity, the same reference numbers will be
used in the drawings to identify similar elements.
[0014] FIG. 1 illustrates a vehicle 10 having an electric braking
system 12. A trailer 14 is attached to the vehicle 10 and the
braking system 12 may be alerted that a trailer 14 is attached. The
trailer 14 also has its own trailer braking system 16. A tire
pressure monitor (TPM) sensor 18 is located in each of the trailer
wheels 20. The ECU 22 is capable of calculating a weight of the
vehicle 10 based upon the footprint of the associated wheel 20
measured by the TPM sensor 18. An electronic control unit (ECU) 22
is associated with the vehicle braking system 12 or the trailer
braking systems 16.
[0015] It will be appreciated that although the description
presented herein is often with respect to a vehicle pulling a
trailer, that the present approaches apply to any kind of primary
vehicle pulling any type of secondary vehicle. That is, the primary
vehicle can be any kind of motorized vehicle such as a passenger
vehicle, while the secondary vehicle can be any type of
non-motorized (or motorized) vehicle such as a trailer.
[0016] When a vehicle 10 has a trailer 14 attached, the braking
system 16 of the trailer 14 must be adjusted based on the weight of
the trailer 14. Trailer load may vary and the exact weight of the
trailer 14 may be unknown to a vehicle operator.
[0017] The approaches described herein provide TPM sensors 18 and
the TPM sensors 18 will be utilized to determine the footprint of
the trailer tires and a vehicle ECU 22 calculate the load and will
use this information to adjust the braking system 16. Some TPM
sensors 18 have the capability to measure the footprint that the
tire 20 in which it is installed is subjected. The footprint, along
with other tire related information, such as pressure, temperature,
and acceleration, are sent in one aspect via RF to the vehicle's
ECU 22. The vehicle ECU 22 uses this information to calculate the
load of each wheel and calculate the entire load of the trailer 14
and adjust the braking system 16 of the trailer 14.
[0018] Some TPM sensors 18, such as eTIS, have the capability to
measure the footprint of the tire 20 in which it is installed. The
footprint, along with other tire related information, such as
pressure, temperature, and acceleration, are sent via RF to the
vehicle's ECU 22.
[0019] Based on the information received from the sensors in the
trailer, the ECU 22 of the vehicle will calculate the load of the
trailer 14 per wheel 20, per axis, per tire or side, and overall
and will use this information to adjust the trailer electric
braking system to its optimal setting.
[0020] In one aspect and when the trailer 14 is attached, the
vehicle 10 will be alerted that a trailer 14 is attached. For
example, a screen on the Driver Information Center (DIC) may
display the alert. In one aspect, the operator is given an
opportunity to enter in a weight of the trailer 14.
[0021] Alternatively, the driver can skip entering the weight and
let the ECU 22 in the vehicle 10 dynamically calculates in the
weight of the trailer 14 during driving. The vehicle ECU 22 will
calculate the trailer 14 weight and will adjust the braking system
16 while the vehicle 10 is in motion. This will ensure that the
braking system 16 is correctly compensating for the weight of the
trailer 14.
[0022] While the vehicle 10 is in motion, the TPM Sensors 18 in the
trailer 14 will measure and transmit the footprint of the tire 20
it is installed in to the vehicle ECU 22.
[0023] Referring now to FIG. 2, one example of how the weight
(load) of the trailer is calculated is described. To illustrate, a
tire 250 rotates in the direction indicated by the arrow labeled
252. A radial line 254 extends from the sensor outward to the edge
of the tire. As the tire rotates, the radial line touches pavement
256 at point 258 and then as the line 254 leaves pavement contacts
the pavement at point 260.
[0024] More specifically, at step 202, the tire pressure sensor
obtains foot print information and this will be eventually used to
dynamically adjust the brake system of the trailer.
[0025] In these regards, it will be appreciated that:
[0026] Pressure=force/surface area, where pressure is the tire
pressure, force is related to the weight of the trailer, and s is
the surface area or footprint.
[0027] The tire pressure monitoring sensor rotates about the tire
as discussed above. The sensor has two shock values during its
rotational period. As the tire rotates, a first shock value of the
sensor is taken as the TPMS sensor first "hits" the pavement at
point 258. That is, an instantaneous value is measured when point
258 is reached. The second shock value is taken when the sensor
leaves the pavement and this is when point 260 is reached. An arc
262 is formed and the length of the arc 262 is related to the
footprint.
[0028] The two shock values (at points 258 and 260) are separated
in time. This time represents a distance and a length of the tire.
The sensor is configured to measure the time per rotation as well
as the centripetal acceleration and gravity. It can be determined,
for example, the distance of one tire rotation (e.g., 2 meters) and
the time for this full rotation (e.g., 20 ms). It also can be
measured by the TPM sensor that the two shock waves are collected 1
ms apart. Consequently, by simple comparison (knowing the overall
length of the tire rotation) and in this example, the length of the
arc is 10 cm and then the area of the arc (footprint) is the square
of the arc length or, in this case, 100 cm.sup.2.
[0029] At step 204, this footprint area information is sent to the
ECU in the vehicle. This can be sent wirelessly, for example, via
an RF signal.
[0030] At step 206 and with a known tire pressure and now the known
area the equation mentioned above can be used and the force (or
weight) of the trailer or on each tire is determined.
[0031] With the weight (load) known, the mass is also easily
determined. Then, an actual braking force can be calculated. In one
aspect, momentum can be defined as mass of the trailer times the
velocity of the trailer. So, in one example, it may be desirable to
go from a high value of momentum to 0 value of momentum. In these
regards, the actual amount of braking force that is needed can be
calculated. For example, if m=1500 kg, and speed 32 20 m/s. then
momentum is 1500 kg times 20 m/s=30000 kg (m)/s. This is the actual
amount of momentum needed to reduce the speed of the trailer to
0.
[0032] At step 208, a signal is sent to the trailer that adjusts
the braking system. This may be the momentum value required to
reduce the trailer speed to a certain value, or may be other scaled
values.
[0033] At step 210, the braking units are adjusted accordingly. It
will also be appreciated that the value calculated and transmitted
by the ECU is used to adjust some other electrical and/or
mechanical element which will actually apply the force and brake
the trailer. For example, the value may adjust a voltage or may
open or close a valve a certain distance to allow brake fluid to be
applied to the brakes of the trailer.
[0034] The approaches described herein have one advantage that
weights of the trailer (and braking forces used by the braking
system) are constantly and automatically being recalculated in real
time. As the speed changes (assuming the trailer has the same mass
or weight), then the actual force used by the braking forces to
stop or slow the trailer will change and this force value is
constantly being updated no matter the speed of the vehicle. These
approaches accommodate the changing amount of force that is needed
to be applied. May be constantly recalculated at predetermined time
intervals. The brake pedal can be used to determine the result
desired. For example, depressing the pedal to a certain level may
indicate that the driver wishes to decelerate the trailer from its
current speed to zero. Other examples are possible.
[0035] Referring now to FIG. 3, one example of a sensor that
utilizes the present approaches is described. The sensor 300
includes a pressure measurement device 302, a processor 304, a
transmitter 306, a receiver 308 and an interface 309. A memory 310
may store computer instructions that are executed on the processor
304 to perform some of the approaches described herein. The TPMS
sensor 300 measures the footprint as has been described above. The
footprint information is sent to the ECU via the transmitter 306
through the interface 309 and an antenna 311. The ECU uses this
information to constantly update braking information as described
above. The sensor 300 also includes an accelerometer 320 (or other
element capable of measuring shocks).
[0036] The interface 309 may perform any appropriate conversion
functions and may be implemented as any appropriate combination of
software or hardware. The transmitter 306 is configured to format
and otherwise prepare signals for transmission and may include
buffers or other components used for transmissions. The receiver
308 is configured to receive transmissions via antenna 311 through
the interface 309. The pressure measurement device 302 obtains
pressure information from a tire. The pressure measurement device
302 may also sense other parameters such as temperature.
[0037] Referring now to FIG. 4, one example of an electronic
control unit 400 in a vehicle is described. The ECU 400 includes a
processor 402, a transmitter 404, a receiver 406, and an interface
409. The ECU 400 might drive a screen or display 413, where user
alerts may be presented to a user. A memory 410 may store computer
instructions that are executed on the processor 404 to perform some
of the approaches described herein.
[0038] In operation, the ECU 400 receives information from the TPM
sensor via antenna 411. The information is obtained by the
processor 402 through interface 409 and receiver 406. The processor
402 then calculates a load. This can be used to determine how to
alter the braking system. For example, if the driver decides to
decelerate from 60 mph to 0, then the weight (or load) of the
trailer may be determined and the force needed to accomplish the
desired result is determined. Instructions as to how to alter the
braking system are sent by the processor 402 through transmitter
404 and the interface 409 via the antenna 411 to the trailer. The
braking system may be adjusted so that this force is applied.
[0039] The interface 409 may perform any appropriate conversion
functions and may be implemented as any appropriate combination of
software or hardware. The transmitter 406 is configured to format
and otherwise prepare signals for transmission and may include
buffers or other components used for transmissions. The receiver
406 is configured to receive transmissions via antenna 411 through
the interface 409. The display 413 is any appropriate display that
is viewable by a driver (or passenger) of the vehicle in which the
ECU is disposed.
[0040] While the best modes for carrying out the invention have
been described in detail the true scope of the disclosure should
not be so limited, since those familiar with the art to which this
invention relates will recognize various alternative designs and
embodiments for practicing the invention within the scope of the
appended claims.
* * * * *